Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

Explain acyclovir, Explain Acyclovir Available in topical, oral, and in...

Explain Acyclovir Available in topical, oral, and intravenous (IV) formulations, acyclovir is used to treat herpes simplex virus (HSV) and varicella-zoster virus (VZV) infectio

Excretion, What is the excretory organ of an agama lizard

What is the excretory organ of an agama lizard

Factor influencing lipid oxidation - temperature, Factors affecting lipid o...

Factors affecting lipid oxidation Temperature In general, the rate of oxidation increases as the temperature is increased. Temperature also influences the relation betw

Eyeball - choroid, CHOROI D - Thin, net like made up of connective ...

CHOROI D - Thin, net like made up of connective tissue, rich in blood vessels. Pigment present, red in rabbit, brown or black in man. It reduces internal reflection.

Define the term- new life for ancient dna, Based on your reading of the art...

Based on your reading of the article "New Life for Ancient DNA" which of the following is a  false statement in regards to the comparison among genes in extinct and living species?

Protein x has an absorptivity of 0.4 ml, Protein X has an absorptivity of 0...

Protein X has an absorptivity of 0.4 mL . mg -1 . cm-1 at 280nm. What is the ab sorbance at 280 nm of a 2.0 mg. mL-1 solutionof protein X ? (Assume the light path is 1 cm).

What is pancreatic lipase, What is Pancreatic lipase Pancreatic lipas...

What is Pancreatic lipase Pancreatic lipase  acts on  the dietary triacylglycerols after it has been incorporated into the mixed micelle  in  the  intestinal lumen. The lipa

Chronic mitral regurgitation-indications for surgery, Chronic Mitral Regurg...

Chronic Mitral Regurgitation :  In chronic mitral regurgitation, the asymptomatic phase is much longer than in mitral stenosis. Onset of symptoms may also mean the onset of l

Define typical ambient air pollutants, Define Typical Ambient Air Pollutant...

Define Typical Ambient Air Pollutants Particulate matter Sulfur containing compounds Organic compounds Nitrogen containing compounds Carbon monoxide

What is rearrangement reaction, PREPARATION OF BENZILIC ACID 1.  What i...

PREPARATION OF BENZILIC ACID 1.  What is rearrangement reaction? The reactions in which the carbon of the molecule is rearranged to give a structural isomer of the original

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd